Many individuals and businesses have replaced physical mail with email. Attachments to email are often used to communicate information that is sent on a predictable schedule or from an expected correspondent. These attachments are used because they can generally convey complexly structured information (e.g., documents, spreadsheets, presentations, videos, etc.) that cannot be readily communicated in the body of an email. Attachments are also useful for communicating documents produced by business and enterprise systems. This is particularly helpful when presenting a consumer with a bill or invoice for a rendered commercial transaction.
While it can be convenient to send information via an attachment to an email, it can be less convenient for the recipient to receive information in this way. The sources of email are legion, originating from businesses, personal correspondents, social media systems, advertisers, marketers, and others. This leads to email accounts receiving enormous amounts of email every day, quickly overwhelming the ability of a user to identify those emails having an attachment and requiring a response.